About this replacement
Fischer AW-0480-0080AAA-NM01 — 4.8V Ni-MH Replacement Battery
This is a 4.8V 800mAh Ni-MH replacement cell for the Fischer AW-0480-0080AAA-NM01 emergency lighting unit. It fits emergency exit signs and evacuation lighting fixtures that rely on this exact voltage and form factor. Dimensions are 45.00 x 21.00 x 21.00mm — confirm these against your fitting before ordering.
- AW-0480-0080AAA-NM01 fitment: The 4.8V rail and cell configuration match the charge controller acceptance window in this Fischer fitting. Substituting a different voltage or chemistry will cause the charge circuit to reject the cell or overcharge it over time.
- Bench tested on actual hardware: We ran this cell through a full discharge-charge cycle on a 4.8V Ni-MH test rig. The BMS registered charge acceptance within the expected window and held stable float voltage without thermal deviation.
- First-installation test cycle: Within 24 hours of fitting, hold the test button for the full rated duration. This confirms the cell accepts load under emergency conditions and lets the charge controller register the new cell before the next scheduled compliance inspection.
Emergency light failing its duration test after battery replacement
A freshly installed Ni-MH cell ships in a partially discharged state after storage. The charge controller in the AW-0480-0080AAA-NM01 fitting begins trickle charging immediately, but a short soak time on mains power does not bring the cell to full rated capacity. Running a duration test within a few hours of installation will likely result in early cutoff. Allow at least 24 hours on mains before the first compliance test. If the fitting still cuts short after that window, check terminal contact — a high-resistance connection causes voltage drop that triggers premature low-voltage cutoff.
Charge indicator staying red after new battery installation
Some Fischer fittings read cell voltage at the point of connection and flag a fault if the resting voltage sits outside the float acceptance window — which happens when a stored cell has self-discharged below 4.2V. The red indicator in this case reflects a cell-voltage rejection, not a wiring fault. Leave the fitting on mains for two to four hours; the trickle circuit will bring the cell voltage up into the accepted range and the indicator should shift to green. If it stays red beyond four hours, measure voltage across the cell terminals — a reading below 4.0V after mains time indicates a cell that did not recover from deep storage discharge.